1. Field of the Invention
The present invention relates to improvements in an actuator. More particularly, the present invention is directed to a linear actuator having improved serviceability and adjustability.
2. The Prior Art
There exist numerous types of linear actuators which are used for tasks where a linear movement is required. Actuators can be used to electrically operate doors, platforms, walls, floors, and booms, for example.
A type of linear actuator includes a ball screw, ball nut, brake and end stops that limit travel of the ball nut on the screw. These components are operably fixed within a pair of coaxially situated reciprocating inner and outer tubes. A drive coupling is staked to one end of the screw, a spacer of the brake is staked to the inside of the outer tube, and the ball nut fixed to a nut adapter which in turn is fixed to the inner tube.
Once staked, these parts become permanently fixed as a single unit and can only be disassembled by cutting off the parts which have been staked. This, however, often results in the destruction of the piece to be salvaged or repaired. Once assembled, if the actuator is or becomes defective or inoperable for its intended purpose, the actuator is scrapped.
This often occurs due to the brake having surfaces which are not configured with the appropriate surface finish and consequently permit unwanted play in their operation. When the brake has play, the actuator will not react smoothly in extending and retracting when supporting a heavy load. This creates a risk to the user as well as damage to the structure and the load carried by the actuator.
There is a need for an improved actuator having improved serviceability and adjustability. There is a need for an actuator with an improved braking system. There is a need for an actuator with interchangeable parts. There is also a need to reduce the cost of actuators and waste in actuator parts.